1. Field of the Invention
The invention is directed to an arrangement for introducing needle thread which is to be wound on the bobbin of a lockstitch sewing machine into a bobbin case slot leading to a thread tensioning device.
2. Description of the Prior Art
U.S. Pat. No. 3,693,566 of The Singer Company issued Sept. 26, 1972 discloses bobbin replenishing mechanism for a lockstitch sewing machine. Such mechanism includes a thread engageable finger that is provided for the purpose of guiding needle thread, which is to be wound upon a bobbin, into a bobbin case slot leading to a thread tensioning device. The thread is moved along the finger and into the mouth of the slot as a seized loop of the thread is moved about the bobbin case by the loop taker, and is supposed to be moved down the slot into the tensioning device by continued motion of the looptaker. However, it sometimes happens that the thread is pulled out of the mouth of the slot after leaving the finger and is caused to move across the slot. As a consequence, the thread fails to enter the tensioning device and the winding of thread onto the bobbin is prevented.
It is an object of the present invention to render bobbin replenishing mechanism effective to so control the movement of needle thread carried by a looptaker as to assure the full introduction of the thread into a bobbin case slot leading to a thread tensioning device and passage of the thread into the tensioning device.
It is another object of the invention to provide bobbin winding mechanism with a thread guiding finger which is effective to hold a limb of a loop of needle thread carried by a looptaker around a bobbin case until movement of the thread by way of a bobbin case slot into a thread tensioning device is assured.
Other objects and advantages of the invention will become apparent during a reading of the specification taken in connection with the accompanying drawings.